Canon Kabushiki Kaisha

Yuki Nishino

Kenji Moribe

Kenichi Shiiba

Kousuke Yamasaki

Daiji Okamura

Satoshi Kudo

Kuniaki Fujimoto

Shin-ichi Hakamada

Itaru Tsuji

Arihiro Saito

Aiko Masada

Misaki Sugie

Shin-Ichi Hakamada

Provided is an aqueous ink for ink jet that can record an image excellent in a color developability by suppressing a bronze phenomenon derived from a carbon black. The aqueous ink for ink jet contains: a self-dispersible carbon black; and a resin particle formed of an acrylic resin. The carbon black has a DBP oil absorption of 120 mL/100 g or more, the acrylic resin particle has a glass transition temperature of 30° C. or more, and a mass ratio of a content (% by mass) of the resin particle to a content (% by mass) of the carbon black is 0.10 times or more to 2.0 times or less.

Aqueous ink, ink cartridge and ink jet recording method

An ink jet recording method is capable of suppressing generation of image streaks and recording a high-quality image when using a recording apparatus equipped with a line head. The ink jet recording method records an image on a recording medium by using an ink jet recording apparatus equipped with a line head. In this method, the line head has a plurality of recording element substrates each having a nozzle array made up of a plurality of nozzles which eject an aqueous ink. The recording element substrates are arranged in a predetermined direction. An average temperature Te (&#xb0; C.) of the aqueous ink ejected from terminal-portion nozzles constituting the terminal portions of the nozzle arrays and an average temperature Tc (&#xb0; C.) of the aqueous ink ejected from center-portion nozzles constituting the center portions of the nozzle arrays satisfy the following relationship: Te&#x3e;Tc.

Ink jet recording method and ink jet recording apparatus

Provided is an ink jet recording method capable of recording an image excellent in color developability while suppressing ink deposition. The ink jet recording method includes ejecting an aqueous ink from an ejection orifice of a recording head based on image data to record an image on a recording medium and ejecting the heated ink to an ink receiving member from the ejection orifice based on preliminary ejection data. The aqueous ink contains a pigment and a resin dispersant for dispersing the pigment and satisfies at least one of requirement (1): the resin dispersant is a water-soluble acrylic resin having an acid value of 135 mgKOH/g or less and requirement (2): the aqueous ink further contains a water-soluble acrylic resin having an acid value of 135 mgKOH/g or less. The pigment is carbon black whose cumulative 50% particle size in volume-based particle size distribution is 80 nm or less.

Provided is an aqueous ink that enables the recording of images having high optical density and excellent toughness and has excellent reliability. An aqueous ink for ink jet includes a pigment, a resin having an anionic group, a salt and a water-soluble organic solvent. The pigment is a self-dispersible pigment in which an anionic group is bonded to the particle surface of carbon black directly or through another atomic group, the resin has a weight-average molecular weight of 20,000 or less, the water-soluble organic solvent includes glycerol and an additional solvent other than glycerol, and the content (% by mass) of the additional solvent relative to the content (% by mass) of glycerol in terms of mass ratio is 0.6 times or less.

An aqueous ink used in an ink jet recording method that uses thermal energy to eject an ink from a recording head includes a copper phthalocyanine pigment and a urethane resin. The urethane resin has a unit derived from a polyisocyanate, a unit derived from a polyether polyol having no acid group, a unit derived from a polyol having an acid group and a unit derived from a polyamine; in the urethane resin, the proportion of the urethane bond relative to the total amount of the urethane bond and the urea bond derived from the polyamine is 90.0% by mole or more to 99.0% by mole or less; and the urethane resin has a weight-average molecular weight of 20,000 or less and an acid value of 50 mg KOH/g or more to 110 mg KOH/g or less.

To provide an aqueous ink that can suppress the dissolution of silicon or a silicon compound contained in a recording head, can be stably, continuously ejected for a long time, and enables the recording of an image having excellent glossiness. An aqueous ink for ink jet includes a pigment, a resin dispersant for dispersing the pigment, an alkanolamine and a urethane resin. The pigment is a solid solution containing C.I. Pigment Red 122 and C.I. Pigment Violet 19, and the proportion (% by mass) of the C.I. Pigment Red 122 is 10% by mass or more to 90% by mass or less based on the total mass of the solid solution.

An ink used for an inkjet recording method for discharging the ink from a recording head by an action of thermal energy contains self-dispersing carbon black, a polyurethane polymer having an acid value of 40 mg KOH/g or more, and an acryl polymer having an acid value of 100 mg KOH/g or more and 200 mg KOH/g or less.

Ink, ink cartridge, and inkjet recording method

An ink jet recording method including recording a secondary color image on a recording medium using a first ink and a second ink, wherein the first ink contains a first self-dispersible pigment having a functional group that contains a phosphonic acid group and is bonded to a particle surface of the pigment, the second ink contains a second self-dispersible pigment having a functional group that contains at least one acidic group of a sulfonic acid group and a carboxylic acid group and is bonded to a particle surface of the pigment. The method includes a step of overlappingly applying the first ink and the second ink in this order to the recording medium. The time difference between applications of the first ink and the second ink to the recording medium is 30 milliseconds or less.

Ink jet recording method

An aqueous ink for ink jet contains a self-dispersible pigment in which a first functional group including a phosphonic acid group and a second functional group including at least one of a carboxylic acid group and a sulfonic acid group are bonded to a particle surface, wherein a surface charge amount derived from the phosphonic acid group included in the above-described first functional group is 0.3 micromoles/mor more, a total surface charge amount derived from the carboxylic acid group and the sulfonic acid group included in the above-described second functional group is 1.0 micromoles/mor more, and a total surface charge amount derived from anionic groups included in the above-described first functional group and the above-described second functional group is 2.0 micromoles/mor more and 8.0 micromoles/mor less.

Aqueous ink, ink cartridge, and ink jet recording method

An ink used for an inkjet recording method for discharging the ink from a recording head by an action of thermal energy contains self-dispersing carbon black, a polyurethane polymer having an acid value of 40 mg KOH/g or more, and polyethylene glycol.

Growing community of inventors

Inagi, Japan

Yuki Nishino